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Yuan PB, Zhan Y, Zhu JH, Ling JH, Chen EZ, Liu WT, Wang LJ, Zhong YX, Chen DQ. Pan-Genome Analysis of Laribacter hongkongensis: Virulence Gene Profiles, Carbohydrate-Active Enzyme Prediction, and Antimicrobial Resistance Characterization. Front Microbiol 2022; 13:862776. [PMID: 35432229 PMCID: PMC9008761 DOI: 10.3389/fmicb.2022.862776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 03/08/2022] [Indexed: 11/13/2022] Open
Abstract
Laribacter hongkongensis is a new emerging foodborne pathogen that causes community-acquired gastroenteritis and traveler’s diarrhea. However, the genetic features of L. hongkongensis have not yet been properly understood. A total of 45 aquatic animal-associated L. hongkongensis strains isolated from intestinal specimens of frogs and grass carps were subjected to whole-genome sequencing (WGS), along with the genome data of 4 reported human clinical strains, the analysis of virulence genes, carbohydrate-active enzymes, and antimicrobial resistance (AMR) determinants were carried out for comprehensively understanding of this new foodborne pathogen. Human clinical strains were genetically more related to some strains from frogs inferred from phylogenetic trees. The distribution of virulence genes and carbohydrate-active enzymes exhibited different patterns among strains of different sources, reflecting their adaption to different host environments and indicating different potentials to infect humans. Thirty-two AMR genes were detected, susceptibility to 18 clinical used antibiotics including aminoglycoside, chloramphenicol, trimethoprim, and sulfa was checked to evaluate the availability of clinical medicines. Resistance to Rifampicin, Cefazolin, ceftazidime, Ampicillin, and ceftriaxone is prevalent in most strains, resistance to tetracycline, trimethoprim-sulfamethoxazole, ciprofloxacin, and levofloxacin are aggregated in nearly half of frog-derived strains, suggesting that drug resistance of frog-derived strains is more serious, and clinical treatment for L. hongkongensis infection should be more cautious.
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Mao W, Lazar N, van Tilbeurgh H, Loiseau PM, Pomel S. Minor Impact of A258D Mutation on Biochemical and Enzymatic Properties of Leishmania infantum GDP-Mannose Pyrophosphorylase. Microorganisms 2022; 10:microorganisms10020231. [PMID: 35208687 PMCID: PMC8877407 DOI: 10.3390/microorganisms10020231] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 01/17/2022] [Indexed: 02/01/2023] Open
Abstract
Background: Leishmaniasis, a vector-borne disease caused by the protozoan parasite from the genus Leishmania, is endemic to tropical and subtropical areas. Few treatments are available against leishmaniasis, with all presenting issues of toxicity, resistance, and/or cost. In this context, the development of new antileishmanial drugs is urgently needed. GDP-mannose pyrophosphorylase (GDP-MP), an enzyme involved in the mannosylation pathway, has been described to constitute an attractive therapeutic target for the development of specific antileishmanial agents. Methods: In this work, we produced, purified, and analyzed the enzymatic properties of the recombinant L. infantum GDP-MP (LiGDP-MP), a single leishmanial GDP-MP that presents mutation of an aspartate instead of an alanine at position 258, which is also the single residue difference with the homolog in L. donovani: LdGDP-MP. Results: The purified LiGDP-MP displayed high substrate and cofactor specificities, a sequential random mechanism of reaction, and the following kinetic constants: Vm at 0.6 µM·min−1, Km from 15–18 µM, kcat from 12.5–13 min−1, and kcat/Km at around 0.8 min−1µM−1. Conclusions: These results show that LiGDP-MP has similar biochemical and enzymatic properties to LdGDP-MP. Further studies are needed to determine the advantage for L. infantum of the A258D residue change in GDP-MP.
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Affiliation(s)
- Wei Mao
- Université Paris-Saclay, CNRS, BioCIS, 92290 Châtenay-Malabry, France; (W.M.); (P.M.L.)
| | - Noureddine Lazar
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France; (N.L.); (H.v.T.)
| | - Herman van Tilbeurgh
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France; (N.L.); (H.v.T.)
| | - Philippe M. Loiseau
- Université Paris-Saclay, CNRS, BioCIS, 92290 Châtenay-Malabry, France; (W.M.); (P.M.L.)
| | - Sébastien Pomel
- Université Paris-Saclay, CNRS, BioCIS, 92290 Châtenay-Malabry, France; (W.M.); (P.M.L.)
- Correspondence:
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3
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Taj A, Jia L, Sha S, Wang C, Ullah H, Haris M, Ma X, Ma Y. Functional analysis and enzyme characterization of Mannose-1-phosphate guanylyl transferase (ManB) from Mycobacterium tuberculosis. Res Microbiol 2021; 173:103884. [PMID: 34644596 DOI: 10.1016/j.resmic.2021.103884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Abstract
Mycobacterium tuberculosis cell wall consist variety of mannose containing glycoconjugates including lipomannan (LM) and lipoarabinomannan (LAM). These lipoglycans are involved in cell wall integrity and play role in virulence of M. tuberculosis by modulating host immune response. GDP-mannose, required for the synthesis of lipoglycans, is catalyzed by enzyme Mannose-1-phosphate guanylyl transferase (ManB). The enzyme with similar function has been studied in variety of species of prokaryotes and eukaryotes. However, biological role of ManB and its enzymatic activity remains uncharacterized in M. tuberculosis. In present study, we elucidated the role of enzyme by constructing manB knockdown strain of M. tuberculosis H37Ra. The manB knockdown decreased the cell growth and also effected the morphology of M. tuberculosis by altering the permeability of cell membrane. These findings provide the understanding on ManB function and suggesting that ManB could be the potential target for novel anti-tuberculosis drug. Furthermore, we also characterized ManB enzyme by establishing 96 well plate colorimetric assay and determined the kinetic properties including initial velocity, optimum temperature, optimum pH and other kinetic parameters. Our established assay will be helpful for further high throughput screening of potential inhibitors against ManB.
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Affiliation(s)
- Ayaz Taj
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Liqiu Jia
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Shanshan Sha
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Chao Wang
- College of Pharmacy, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Hayan Ullah
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Muhammad Haris
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Xiaochi Ma
- College of Pharmacy, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
| | - Yufang Ma
- Department of Biochemistry and Molecular Biology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China; Department of Microbiology, Dalian Medical University, 9 W. Lushun South Road, Dalian, 116044, China.
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4
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Koeksoy E, Bezuidt OM, Bayer T, Chan CS, Emerson D. Zetaproteobacteria Pan-Genome Reveals Candidate Gene Cluster for Twisted Stalk Biosynthesis and Export. Front Microbiol 2021; 12:679409. [PMID: 34220764 PMCID: PMC8250860 DOI: 10.3389/fmicb.2021.679409] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 05/06/2021] [Indexed: 12/15/2022] Open
Abstract
Twisted stalks are morphologically unique bacterial extracellular organo-metallic structures containing Fe(III) oxyhydroxides that are produced by microaerophilic Fe(II)-oxidizers belonging to the Betaproteobacteria and Zetaproteobacteria. Understanding the underlying genetic and physiological mechanisms of stalk formation is of great interest based on their potential as novel biogenic nanomaterials and their relevance as putative biomarkers for microbial Fe(II) oxidation on ancient Earth. Despite the recognition of these special biominerals for over 150 years, the genetic foundation for the stalk phenotype has remained unresolved. Here we present a candidate gene cluster for the biosynthesis and secretion of the stalk organic matrix that we identified with a trait-based analyses of a pan-genome comprising 16 Zetaproteobacteria isolate genomes. The “stalk formation in Zetaproteobacteria” (sfz) cluster comprises six genes (sfz1-sfz6), of which sfz1 and sfz2 were predicted with functions in exopolysaccharide synthesis, regulation, and export, sfz4 and sfz6 with functions in cell wall synthesis manipulation and carbohydrate hydrolysis, and sfz3 and sfz5 with unknown functions. The stalk-forming Betaproteobacteria Ferriphaselus R-1 and OYT-1, as well as dread-forming Zetaproteobacteria Mariprofundus aestuarium CP-5 and Mariprofundus ferrinatatus CP-8 contain distant sfz gene homologs, whereas stalk-less Zetaproteobacteria and Betaproteobacteria lack the entire gene cluster. Our pan-genome analysis further revealed a significant enrichment of clusters of orthologous groups (COGs) across all Zetaproteobacteria isolate genomes that are associated with the regulation of a switch between sessile and motile growth controlled by the intracellular signaling molecule c-di-GMP. Potential interactions between stalk-former unique transcription factor genes, sfz genes, and c-di-GMP point toward a c-di-GMP regulated surface attachment function of stalks during sessile growth.
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Affiliation(s)
- Elif Koeksoy
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States.,Leibniz Institute DSMZ (German Collection of Microorganisms and Cell Cultures), Braunschweig, Germany
| | - Oliver M Bezuidt
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
| | - Timm Bayer
- Geomicrobiology Group, Center for Applied Geoscience, University of Tübingen, Tübingen, Germany
| | - Clara S Chan
- Department of Earth Sciences, University of Delaware, Newark, DE, United States.,School of Marine Sciences and Policy, University of Delaware, Newark, DE, United States
| | - David Emerson
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States
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5
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Marmont LS, Whitfield GB, Pfoh R, Williams RJ, Randall TE, Ostaszewski A, Razvi E, Groves RA, Robinson H, Nitz M, Parsek MR, Lewis IA, Whitney JC, Harrison JJ, Howell PL. PelX is a UDP- N-acetylglucosamine C4-epimerase involved in Pel polysaccharide-dependent biofilm formation. J Biol Chem 2020; 295:11949-11962. [PMID: 32601062 PMCID: PMC7443510 DOI: 10.1074/jbc.ra120.014555] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/24/2020] [Indexed: 12/15/2022] Open
Abstract
Pel is a GalNAc-rich bacterial polysaccharide that contributes to the structure and function of Pseudomonas aeruginosa biofilms. The pelABCDEFG operon is highly conserved among diverse bacterial species, and Pel may therefore be a widespread biofilm determinant. Previous annotation of pel gene clusters has helped us identify an additional gene, pelX, that is present adjacent to pelABCDEFG in >100 different bacterial species. The pelX gene is predicted to encode a member of the short-chain dehydrogenase/reductase (SDR) superfamily, but its potential role in Pel-dependent biofilm formation is unknown. Herein, we have used Pseudomonas protegens Pf-5 as a model to elucidate PelX function as Pseudomonas aeruginosa lacks a pelX homologue in its pel gene cluster. We found that P. protegens forms Pel-dependent biofilms; however, despite expression of pelX under these conditions, biofilm formation was unaffected in a ΔpelX strain. This observation led us to identify a pelX paralogue, PFL_5533, which we designate here PgnE, that appears to be functionally redundant to pelX In line with this, a ΔpelX ΔpgnE double mutant was substantially impaired in its ability to form Pel-dependent biofilms. To understand the molecular basis for this observation, we determined the structure of PelX to 2.1 Å resolution. The structure revealed that PelX resembles UDP-GlcNAc C4-epimerases. Using 1H NMR analysis, we show that PelX catalyzes the epimerization between UDP-GlcNAc and UDP-GalNAc. Our results indicate that Pel-dependent biofilm formation requires a UDP-GlcNAc C4-epimerase that generates the UDP-GalNAc precursors required by the Pel synthase machinery for polymer production.
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Affiliation(s)
- Lindsey S Marmont
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Gregory B Whitfield
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Roland Pfoh
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Rohan J Williams
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Trevor E Randall
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | | | - Erum Razvi
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Ryan A Groves
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - Howard Robinson
- Photon Science Division, Brookhaven National Laboratory, Upton, New York, USA
| | - Mark Nitz
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Matthew R Parsek
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Ian A Lewis
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - John C Whitney
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Joe J Harrison
- Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada
| | - P Lynne Howell
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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6
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Pomel S, Mao W, Ha-Duong T, Cavé C, Loiseau PM. GDP-Mannose Pyrophosphorylase: A Biologically Validated Target for Drug Development Against Leishmaniasis. Front Cell Infect Microbiol 2019; 9:186. [PMID: 31214516 PMCID: PMC6554559 DOI: 10.3389/fcimb.2019.00186] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 05/15/2019] [Indexed: 01/02/2023] Open
Abstract
Leishmaniases are neglected tropical diseases that threaten about 350 million people in 98 countries around the world. In order to find new antileishmanial drugs, an original approach consists in reducing the pathogenic effect of the parasite by impairing the glycoconjugate biosynthesis, necessary for parasite recognition and internalization by the macrophage. Some proteins appear to be critical in this way, and one of them, the GDP-Mannose Pyrophosphorylase (GDP-MP), is an attractive target for the design of specific inhibitors as it is essential for Leishmania survival and it presents significant differences with the host counterpart. Two GDP-MP inhibitors, compounds A and B, have been identified in two distinct studies by high throughput screening and by a rational approach based on molecular modeling, respectively. Compound B was found to be the most promising as it exhibited specific competitive inhibition of leishmanial GDP-MP and antileishmanial activities at the micromolar range with interesting selectivity indexes, as opposed to compound A. Therefore, compound B can be used as a pharmacological tool for the development of new specific antileishmanial drugs.
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Affiliation(s)
- Sébastien Pomel
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Wei Mao
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Tâp Ha-Duong
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Christian Cavé
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - Philippe M Loiseau
- UMR 8076 CNRS BioCIS, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
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7
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Physiological and proteomic analysis of Nostoc flagelliforme in response to alkaline pH shift for polysaccharide accumulation. ALGAL RES 2019. [DOI: 10.1016/j.algal.2019.101444] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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8
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Ahmad L, Plancqueel S, Dubosclard V, Lazar N, Ghattas W, Li de la Sierra‐Gallay I, Tilbeurgh H, Salmon L. Crystal structure of phosphomannose isomerase from
Candida albicans
complexed with 5‐phospho‐
d
‐arabinonhydrazide. FEBS Lett 2018; 592:1667-1680. [DOI: 10.1002/1873-3468.13059] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 04/06/2018] [Accepted: 04/11/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Lama Ahmad
- Equipe de Chimie Bioorganique et Bioinorganique Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO) CNRS UMR8182 LabEx LERMIT Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Stéphane Plancqueel
- Institut de Biologie Intégrative de la Cellule (I2BC) CNRS UMR9198 Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Virginie Dubosclard
- Equipe de Chimie Bioorganique et Bioinorganique Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO) CNRS UMR8182 LabEx LERMIT Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Noureddine Lazar
- Institut de Biologie Intégrative de la Cellule (I2BC) CNRS UMR9198 Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Wadih Ghattas
- Equipe de Chimie Bioorganique et Bioinorganique Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO) CNRS UMR8182 LabEx LERMIT Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Inès Li de la Sierra‐Gallay
- Institut de Biologie Intégrative de la Cellule (I2BC) CNRS UMR9198 Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Herman Tilbeurgh
- Institut de Biologie Intégrative de la Cellule (I2BC) CNRS UMR9198 Université Paris‐Saclay Université Paris‐Sud Orsay France
| | - Laurent Salmon
- Equipe de Chimie Bioorganique et Bioinorganique Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO) CNRS UMR8182 LabEx LERMIT Université Paris‐Saclay Université Paris‐Sud Orsay France
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9
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Han PP, Guo RJ, Shen SG, Yan RR, Wu YK, Yao SY, Wang HY, Jia SR. Proteomic profiling of Nostoc flagelliforme reveals the common mechanism in promoting polysaccharide production by different light qualities. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2017.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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10
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Urtuvia V, Maturana N, Acevedo F, Peña C, Díaz-Barrera A. Bacterial alginate production: an overview of its biosynthesis and potential industrial production. World J Microbiol Biotechnol 2017; 33:198. [DOI: 10.1007/s11274-017-2363-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/01/2017] [Indexed: 10/18/2022]
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11
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Biochemical analysis of leishmanial and human GDP-Mannose Pyrophosphorylases and selection of inhibitors as new leads. Sci Rep 2017; 7:751. [PMID: 28389670 PMCID: PMC5429698 DOI: 10.1038/s41598-017-00848-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 03/16/2017] [Indexed: 12/12/2022] Open
Abstract
Leishmaniases are an ensemble of diseases caused by the protozoan parasite of the genus Leishmania. Current antileishmanial treatments are limited and present main issues of toxicity and drug resistance emergence. Therefore, the generation of new inhibitors specifically directed against a leishmanial target is an attractive strategy to expand the chemotherapeutic arsenal. GDP-Mannose Pyrophosphorylase (GDP-MP) is a prominent therapeutic target involved in host-parasite recognition which has been described to be essential for parasite survival. In this work, we produced and purified GDP-MPs from L. mexicana (LmGDP-MP), L. donovani (LdGDP-MP), and human (hGDP-MP), and compared their enzymatic properties. From a rationale design of 100 potential inhibitors, four compounds were identified having a promising and specific inhibitory effect on parasite GDP-MP and antileishmanial activities, one of them exhibits a competitive inhibition on LdGDP-MP and belongs to the 2-substituted quinoline series.
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12
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Han PP, Yao SY, Guo RJ, Yan RR, Wu YK, Shen SG, Jia SR. Influence of culture conditions on extracellular polysaccharide production and the activities of enzymes involved in the polysaccharide synthesis of Nostoc flagelliforme. RSC Adv 2017. [DOI: 10.1039/c7ra07982f] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Important enzymes influencing the production ofNostoc flagelliformeEPS were investigated under different culture conditions.
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Affiliation(s)
- Pei-pei Han
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
| | - Shun-yu Yao
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
| | - Rong-jun Guo
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
| | - Rong-rong Yan
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
| | - Yi-kai Wu
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
| | - Shi-gang Shen
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
| | - Shi-ru Jia
- Key Laboratory of Industrial Fermentation Microbiology
- Ministry of Education
- College of Biotechnology
- Tianjin University of Science and Technology
- Tianjin 300457
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13
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Gresh N, Perahia D, de Courcy B, Foret J, Roux C, El-Khoury L, Piquemal JP, Salmon L. Complexes of a Zn-metalloenzyme binding site with hydroxamate-containing ligands. A case for detailed benchmarkings of polarizable molecular mechanics/dynamics potentials when the experimental binding structure is unknown. J Comput Chem 2016; 37:2770-2782. [DOI: 10.1002/jcc.24503] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 08/31/2016] [Accepted: 09/04/2016] [Indexed: 12/15/2022]
Affiliation(s)
- Nohad Gresh
- Laboratoire de Chimie Théorique; Sorbonne Universités; UPMC, UMR 7616 CNRS Paris France
- Chemistry and Biology, Nucleo(s)tides and Immunology for Therapy (CBNIT); UMR 8601 CNRS, UFR Biomédicale; Paris France
| | - David Perahia
- Laboratoire de Biologie et Pharmacologie Appliquées (LBPA), UMR 8113; Ecole Normale Supérieure Cachan France
| | - Benoit de Courcy
- Laboratoire de Chimie Théorique; Sorbonne Universités; UPMC, UMR 7616 CNRS Paris France
- Chemistry and Biology, Nucleo(s)tides and Immunology for Therapy (CBNIT); UMR 8601 CNRS, UFR Biomédicale; Paris France
| | - Johanna Foret
- Laboratoire de Chimie Bioorganique et Bioinorganique; Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Univ Paris-Saclay, Univ Paris-Sud, UMR 8182 CNRS; rue du Doyen Georges Poitou Orsay F-91405 France
| | - Céline Roux
- Laboratoire de Chimie Bioorganique et Bioinorganique; Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Univ Paris-Saclay, Univ Paris-Sud, UMR 8182 CNRS; rue du Doyen Georges Poitou Orsay F-91405 France
| | - Lea El-Khoury
- Laboratoire de Chimie Théorique; Sorbonne Universités; UPMC, UMR 7616 CNRS Paris France
- Centre d'Analyses et de Recherche; UR EGFEM, LSIM, Faculté de Sciences, Saint Joseph University of Beirut; BP 11-514, Riad El Solh Beirut 1116-2050 Lebanon
| | - Jean-Philip Piquemal
- Laboratoire de Chimie Théorique; Sorbonne Universités; UPMC, UMR 7616 CNRS Paris France
- Department of Biomolecular Engineering; The University of Texas at Austin; Texas 78712
| | - Laurent Salmon
- Laboratoire de Chimie Bioorganique et Bioinorganique; Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Univ Paris-Saclay, Univ Paris-Sud, UMR 8182 CNRS; rue du Doyen Georges Poitou Orsay F-91405 France
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14
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Choudhary GS, Yao X, Wang J, Peng B, Bader RA, Ren D. Human Granulocyte Macrophage Colony-Stimulating Factor Enhances Antibiotic Susceptibility of Pseudomonas aeruginosa Persister Cells. Sci Rep 2015; 5:17315. [PMID: 26616387 PMCID: PMC4663479 DOI: 10.1038/srep17315] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 10/28/2015] [Indexed: 12/11/2022] Open
Abstract
Bacterial persister cells are highly tolerant to antibiotics and cause chronic infections. However, little is known about the interaction between host immune systems with this subpopulation of metabolically inactive cells, and direct effects of host immune factors (in the absence of immune cells) on persister cells have not been studied. Here we report that human granulocyte macrophage-colony stimulating factor (GM-CSF) can sensitize the persister cells of Pseudomonas aeruginosa PAO1 and PDO300 to multiple antibiotics including ciprofloxacin, tobramycin, tetracycline, and gentamicin. GM-CSF also sensitized the biofilm cells of P. aeruginosa PAO1 and PDO300 to tobramycin in the presence of biofilm matrix degrading enzymes. The DNA microarray and qPCR results indicated that GM-CSF induced the genes for flagellar motility and pyocin production in the persister cells, but not the normal cells of P. aeruginosa PAO1. Consistently, the supernatants from GM-CSF treated P. aeruginosa PAO1 persister cell suspensions were found cidal to the pyocin sensitive strain P. aeruginosa PAK. Collectively, these findings suggest that host immune factors and bacterial persisters may directly interact, leading to enhanced susceptibility of persister cells to antibiotics.
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Affiliation(s)
- Geetika S Choudhary
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA.,Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Xiangyu Yao
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA.,Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Jing Wang
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA.,Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Bo Peng
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA.,Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Rebecca A Bader
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA.,Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Dacheng Ren
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA.,Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA.,Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244, USA.,Department of Biology, Syracuse University, Syracuse, NY 13244, USA
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15
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Akutsu JI, Zhang Z, Morita R, Kawarabayasi Y. Identification and characterization of a thermostable bifunctional enzyme with phosphomannose isomerase and sugar-1-phosphate nucleotidylyltransferase activities from a hyperthermophilic archaeon, Pyrococcus horikoshii OT3. Extremophiles 2015; 19:1077-85. [PMID: 26290359 DOI: 10.1007/s00792-015-0779-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 08/03/2015] [Indexed: 10/23/2022]
Abstract
Mannosylglycerate is known as a compatible solute, and plays important roles for salinity adaptation and high temperature stability of microorganisms. In the gene cluster for the mannosylglycerate biosynthetic pathway predicted from the genomic data of Pyrococcus horikoshii OT3, the PH0925 protein was found as a putative bifunctional enzyme with phosphomannose isomerase (PMI) and mannose-1-phosphate guanylyltransferase (Man-1-P GTase) activities, which can synthesize GDP-mannose when accompanied by a phosphomannomutase/phosphoglucomutase (PMM/PGM) enzyme (PH0923). The recombinant PH0925 protein, expressed in E. coli, exhibited both expected PMI and Man-1-P GTase activities, as well as absolute thermostability; 95 °C was the optimum reaction temperature. According to the guanylyltransferase activity (GTase) of the PH0925 protein, it was found that the protein can catalyze glucose-1-phosphate (Glc-1-P) and glucosamine-1-phosphate (GlcN-1-P) in addition to Man-1-P. The analyses of C-terminus-truncated forms of the PH0925 protein indicated that sugar-1-phosphate nucleotidylyltransferase (Sugar-1-P NTase) activity was located in the region from the N-terminus to the 345th residue, and that the C-terminal 114 residue region of the PH0925 protein inhibited the Man-1-P GTase activity. Conversely, the PMI activity was abolished by deletion of the C-terminal 14 residues. This is the first report of a thermostable enzyme with both PMI and multiple Sugar-1-P NTase activities.
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Affiliation(s)
- Jun-ichi Akutsu
- National Institute of Advanced Industrial Science and Technology (AIST), Nakoji 3-11-46, Amagasaki, Hyogo, 661-0974, Japan
| | - Zilian Zhang
- State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, 361005, People's Republic of China
| | - Rihito Morita
- Laboratory on Functional Genomics of Extremophiles, Faculty of Agriculture, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka, 812-8581, Japan
| | - Yutaka Kawarabayasi
- National Institute of Advanced Industrial Science and Technology (AIST), Nakoji 3-11-46, Amagasaki, Hyogo, 661-0974, Japan. .,Laboratory on Functional Genomics of Extremophiles, Faculty of Agriculture, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka, Fukuoka, 812-8581, Japan.
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16
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Peng L, Qiao S, Xu Z, Guan F, Ding Z, Gu Z, Zhang L, Shi G. Effects of culture conditions on monosaccharide composition of Ganoderma lucidum exopolysaccharide and on activities of related enzymes. Carbohydr Polym 2015; 133:104-9. [PMID: 26344261 DOI: 10.1016/j.carbpol.2015.07.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 07/06/2015] [Accepted: 07/07/2015] [Indexed: 11/29/2022]
Abstract
We investigated the relationship between monosaccharide composition of Ganoderma lucidum exopolysaccharide (EPS) and activities of EPS synthesis enzymes under various culture temperatures and initial pH values. The mole percentages of three major EPS monosaccharides, glucose, galactose and mannose, varied depending on culture conditions and the resulting EPS displayed differing anti-tumor activities. In nine tested enzymes, higher enzyme activities were correlated with higher temperature and lower initial pH. Altered mole percentages of galactose and mannose under various culture conditions were associated with activities of α-phosphoglucomutase (PGM) and phosphoglucose isomerase (PGI), respectively, and that of mannose was also associated with phosphomannose isomerase (PMI) activity only under various pH. Our findings suggest that mole percentages of G. lucidum EPS monosaccharides can be manipulated by changes of culture conditions that affect enzyme activities, and that novel fermentation strategies based on this approach may enhance production and biological activity of EPS.
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Affiliation(s)
- Lin Peng
- Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Shuangkui Qiao
- Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi 214122, China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
| | - Zhenghong Xu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Feng Guan
- Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Zhongyang Ding
- Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, & School of Biotechnology, Jiangnan University, Wuxi 214122, China; National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
| | - Zhenghua Gu
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
| | - Liang Zhang
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
| | - Guiyang Shi
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Wuxi 214122, China
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17
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Van Schaftingen E, Veiga-da-Cunha M, Linster CL. Enzyme complexity in intermediary metabolism. J Inherit Metab Dis 2015; 38:721-7. [PMID: 25700988 DOI: 10.1007/s10545-015-9821-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 01/30/2015] [Accepted: 02/03/2015] [Indexed: 10/24/2022]
Abstract
A good appraisal of the function of enzymes is essential for the understanding of inborn errors of metabolism. However, it is clear now that the 'one gene, one enzyme, one catalytic function' rule oversimplifies the actual situation. Genes often encode several related proteins, which may differ in their subcellular localisation, regulation or function. Furthermore, enzymes often show several catalytic activities. In some cases, this is because they are multifunctional, possessing two or more different active sites that catalyse different, physiologically related reactions. In enzymes with broad specificity or in multispecificity enzymes, a single type of catalytic site performs the same reaction on different physiological substrates at similar rates. Enzymes that act physiologically in only one reaction often show nonetheless substrate promiscuity: they act at low rates on compounds that resemble their physiological substrate(s), thus forming non-classical metabolites, which are in some cases eliminated by metabolite repair. In addition to their catalytic role, enzymes may have moonlighting functions, i.e. non-catalytic functions that are most often not related with their catalytic activity. Deficiency in such functions may participate in the phenotype of inborn errors of metabolism. Evolution has also made that some enzymes have lost their catalytic activity to become allosteric proteins.
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Affiliation(s)
- Emile Van Schaftingen
- Welbio and de Duve Institute, Université catholique de Louvain, Avenue Hippocrate 75, 1200, Brussels, Belgium,
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18
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Abstract
Moonlighting proteins comprise a class of multifunctional proteins in which a single polypeptide chain performs multiple physiologically relevant biochemical or biophysical functions. Almost 300 proteins have been found to moonlight. The known examples of moonlighting proteins include diverse types of proteins, including receptors, enzymes, transcription factors, adhesins and scaffolds, and different combinations of functions are observed. Moonlighting proteins are expressed throughout the evolutionary tree and function in many different biochemical pathways. Some moonlighting proteins can perform both functions simultaneously, but for others, the protein's function changes in response to changes in the environment. The diverse examples of moonlighting proteins already identified, and the potential benefits moonlighting proteins might provide to the organism, such as through coordinating cellular activities, suggest that many more moonlighting proteins are likely to be found. Continuing studies of the structures and functions of moonlighting proteins will aid in predicting the functions of proteins identified through genome sequencing projects, in interpreting results from proteomics experiments, in understanding how different biochemical pathways interact in systems biology, in annotating protein sequence and structure databases, in studies of protein evolution and in the design of proteins with novel functions.
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19
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Laverty G, Gorman SP, Gilmore BF. Biomolecular Mechanisms of Pseudomonas aeruginosa and Escherichia coli Biofilm Formation. Pathogens 2014; 3:596-632. [PMID: 25438014 PMCID: PMC4243431 DOI: 10.3390/pathogens3030596] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/10/2014] [Accepted: 07/14/2014] [Indexed: 12/13/2022] Open
Abstract
Pseudomonas aeruginosa and Escherichia coli are the most prevalent Gram-negative biofilm forming medical device associated pathogens, particularly with respect to catheter associated urinary tract infections. In a similar manner to Gram-positive bacteria, Gram-negative biofilm formation is fundamentally determined by a series of steps outlined more fully in this review, namely adhesion, cellular aggregation, and the production of an extracellular polymeric matrix. More specifically this review will explore the biosynthesis and role of pili and flagella in Gram-negative adhesion and accumulation on surfaces in Pseudomonas aeruginosa and Escherichia coli. The process of biofilm maturation is compared and contrasted in both species, namely the production of the exopolysaccharides via the polysaccharide synthesis locus (Psl), pellicle Formation (Pel) and alginic acid synthesis in Pseudomonas aeruginosa, and UDP-4-amino-4-deoxy-l-arabinose and colonic acid synthesis in Escherichia coli. An emphasis is placed on the importance of the LuxR homologue sdiA; the luxS/autoinducer-II; an autoinducer-III/epinephrine/norepinephrine and indole mediated Quorum sensing systems in enabling Gram-negative bacteria to adapt to their environments. The majority of Gram-negative biofilms consist of polysaccharides of a simple sugar structure (either homo- or heteropolysaccharides) that provide an optimum environment for the survival and maturation of bacteria, allowing them to display increased resistance to antibiotics and predation.
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Affiliation(s)
- Garry Laverty
- Biomaterials, Biofilm and Infection Control Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
| | - Sean P Gorman
- Biomaterials, Biofilm and Infection Control Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
| | - Brendan F Gilmore
- Biomaterials, Biofilm and Infection Control Research Group, School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
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20
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Hay ID, Wang Y, Moradali MF, Rehman ZU, Rehm BHA. Genetics and regulation of bacterial alginate production. Environ Microbiol 2014; 16:2997-3011. [DOI: 10.1111/1462-2920.12389] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Revised: 12/18/2013] [Accepted: 12/22/2013] [Indexed: 12/31/2022]
Affiliation(s)
- Iain D. Hay
- Institute of Fundamental Sciences; Massey University; Palmerston North 4442 New Zealand
| | - Yajie Wang
- Institute of Fundamental Sciences; Massey University; Palmerston North 4442 New Zealand
| | - Mohammed F. Moradali
- Institute of Fundamental Sciences; Massey University; Palmerston North 4442 New Zealand
| | - Zahid U. Rehman
- Institute of Fundamental Sciences; Massey University; Palmerston North 4442 New Zealand
| | - Bernd H. A. Rehm
- Institute of Fundamental Sciences; Massey University; Palmerston North 4442 New Zealand
- MacDiarmid Institute for Advanced Materials and Nanotechnology; Massey University; Palmerston North 4442 New Zealand
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21
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Hay ID, Ur Rehman Z, Moradali MF, Wang Y, Rehm BHA. Microbial alginate production, modification and its applications. Microb Biotechnol 2013; 6:637-50. [PMID: 24034361 PMCID: PMC3815931 DOI: 10.1111/1751-7915.12076] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 06/25/2013] [Accepted: 07/06/2013] [Indexed: 11/29/2022] Open
Abstract
Alginate is an important polysaccharide used widely in the food, textile, printing and pharmaceutical industries for its viscosifying, and gelling properties. All commercially produced alginates are isolated from farmed brown seaweeds. These algal alginates suffer from heterogeneity in composition and material properties. Here, we will discuss alginates produced by bacteria; the molecular mechanisms involved in their biosynthesis; and the potential to utilize these bacterially produced or modified alginates for high-value applications where defined material properties are required.
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Affiliation(s)
- Iain D Hay
- Institute of Fundamental Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand
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22
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Farrell EK, Tipton PA. Functional characterization of AlgL, an alginate lyase from Pseudomonas aeruginosa. Biochemistry 2012; 51:10259-66. [PMID: 23215237 DOI: 10.1021/bi301425r] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alginate lyase (AlgL) catalyzes the cleavage of the polysaccharide alginate through a β-elimination reaction. In Pseudomonas aeruginosa, algL is part of the alginate biosynthetic operon, and although it is required for alginate biosynthesis, it is not clear why. Steady-state kinetic studies were performed to characterize its substrate specificity and revealed that AlgL operates preferentially on nonacetylated alginate or its precursor mannuronan. Mature alginate is secreted as a partially acetylated polysaccharide, so this observation is consistent with suggestions that AlgL serves to degrade mislocalized alginate that is trapped in the periplasmic space. The k(cat)/K(m) for the reaction increased linearly with the number of residues in the substrate, from 2.1 × 10(5) M(-1) s(-1) for the substrate containing 16 residues to 7.9 × 10(6) M(-1) s(-1) for the substrate with 280 residues. Over the same substrate size range, k(cat) varied between 10 and 30 s(-1). The variation in k(cat)/K(m) with substrate length suggests that AlgL operates in a processive manner. AlgL displayed a surprising lack of stereospecificity, in that it was able to catalyze cleavage adjacent to either mannuronate or guluronate residues in alginate. Thus, the enzyme is able to remove the C5 proton from both mannuronate and guluronate, which are C5 epimers. Exhaustive digestion of alginate by AlgL generated dimeric and trimeric products, which were characterized by (1)H nuclear magnetic resonance spectroscopy and mass spectrometry. Rapid-mixing chemical quench studies revealed that there was no lag in dimer or trimer production, indicating that AlgL operates as an exopolysaccharide lyase.
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Affiliation(s)
- Emma K Farrell
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
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23
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Protein Glycosylation in Aspergillus fumigatus Is Essential for Cell Wall Synthesis and Serves as a Promising Model of Multicellular Eukaryotic Development. Int J Microbiol 2011; 2012:654251. [PMID: 21977037 PMCID: PMC3184424 DOI: 10.1155/2012/654251] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 07/19/2011] [Indexed: 02/05/2023] Open
Abstract
Glycosylation is a conserved posttranslational modification that is found in all eukaryotes, which helps generate proteins with multiple functions. Our knowledge of glycosylation mainly comes from the investigation of the yeast Saccharomyces cerevisiae and mammalian cells. However, during the last decade, glycosylation in the human pathogenic mold Aspergillus fumigatus has drawn significant attention. It has been revealed that glycosylation in A. fumigatus is crucial for its growth, cell wall synthesis, and development and that the process is more complicated than that found in the budding yeast S. cerevisiae. The present paper implies that the investigation of glycosylation in A. fumigatus is not only vital for elucidating the mechanism of fungal cell wall synthesis, which will benefit the design of new antifungal therapies, but also helps to understand the role of protein glycosylation in the development of multicellular eukaryotes. This paper describes the advances in functional analysis of protein glycosylation in A. fumigatus.
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24
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Rajesh T, Song E, Kim JN, Lee BR, Kim EJ, Park SH, Kim YG, Yoo D, Park HY, Choi YH, Kim BG, Yang YH. Inactivation of phosphomannose isomerase gene abolishes sporulation and antibiotic production in Streptomyces coelicolor. Appl Microbiol Biotechnol 2011; 93:1685-93. [PMID: 21952939 DOI: 10.1007/s00253-011-3581-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 08/17/2011] [Accepted: 09/14/2011] [Indexed: 11/30/2022]
Abstract
Phosphomannose isomerases (PMIs) in bacteria and fungi catalyze the reversible conversion of D-fructose-6-phosphate to D-mannose-6-phosphate during biosynthesis of GDP-mannose, which is the main intermediate in the mannosylation of important cell wall components, glycoproteins, and certain glycolipids. In the present study, the kinetic parameters of PMI from Streptomyces coelicolor were obtained, and its function on antibiotic production and sporulation was studied. manA (SCO3025) encoding PMI in S. coelicolor was deleted by insertional inactivation. Its mutant (S. coelicolor∆manA) was found to exhibit a bld-like phenotype. Additionally, S. coelicolor∆manA failed to produce the antibiotics actinorhodin and red tripyrolle undecylprodigiosin in liquid media. To identify the function of manA, the gene was cloned and expressed in Escherichia coli BL21 (DE3). The purified recombinant ManA exhibited PMI activity (K(cat)/K(m) (mM(-1) s(-1) = 0.41 for D-mannose-6-phosphate), but failed to show GDP-D-mannose pyrophosphorylase [GMP (ManC)] activity. Complementation analysis with manA from S. coelicolor or E. coli resulted in the recovery of bld-like phenotype of S. coelicolor∆manA. SCO3026, another ORF that encodes a protein with sequence similarity towards bifunctional PMI and GMP, was also tested for its ability to function as an alternate ManA. However, the purified protein of SCO3026 failed to exhibit both PMI and GMP activity. The present study shows that enzymes involved in carbohydrate metabolism could control cellular differentiation as well as the production of secondary metabolites.
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Affiliation(s)
- Thangamani Rajesh
- Department of Microbial Engineering, College of Engineering, Konkuk University, Seoul, South Korea
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25
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Gresh N, de Courcy B, Piquemal JP, Foret J, Courtiol-Legourd S, Salmon L. Polarizable Water Networks in Ligand–Metalloprotein Recognition. Impact on the Relative Complexation Energies of Zn-Dependent Phosphomannose Isomerase with d-Mannose 6-Phosphate Surrogates. J Phys Chem B 2011; 115:8304-16. [DOI: 10.1021/jp2024654] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nohad Gresh
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR8601 CNRS, Univ Paris Descartes, UFR Biomédicale, Faculté de Médecine de Paris, F-75006, Paris, France
| | - Benoit de Courcy
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, UMR8601 CNRS, Univ Paris Descartes, UFR Biomédicale, Faculté de Médecine de Paris, F-75006, Paris, France
- Laboratoire de Chimie Théorique, UPMC Univ Paris 06, UMR7616, F-75252, Paris, France
- Laboratoire de Chimie Théorique, CNRS, UMR7616, F-75252, Paris, France
| | - Jean-Philip Piquemal
- Laboratoire de Chimie Théorique, UPMC Univ Paris 06, UMR7616, F-75252, Paris, France
- Laboratoire de Chimie Théorique, CNRS, UMR7616, F-75252, Paris, France
| | - Johanna Foret
- Laboratoire de Chimie Bioorganique et Bioinorganique, Univ Paris-Sud, ICMMO, UMR8182, F-91405, Orsay, France
- Laboratoire de Chimie Bioorganique et Bioinorganique, CNRS, ICMMO, UMR8182, F-91405, Orsay, France
| | - Stéphanie Courtiol-Legourd
- Laboratoire de Chimie Bioorganique et Bioinorganique, Univ Paris-Sud, ICMMO, UMR8182, F-91405, Orsay, France
- Laboratoire de Chimie Bioorganique et Bioinorganique, CNRS, ICMMO, UMR8182, F-91405, Orsay, France
| | - Laurent Salmon
- Laboratoire de Chimie Bioorganique et Bioinorganique, Univ Paris-Sud, ICMMO, UMR8182, F-91405, Orsay, France
- Laboratoire de Chimie Bioorganique et Bioinorganique, CNRS, ICMMO, UMR8182, F-91405, Orsay, France
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26
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Roux C, Bhatt F, Foret J, de Courcy B, Gresh N, Piquemal JP, Jeffery CJ, Salmon L. The reaction mechanism of type I phosphomannose isomerases: new information from inhibition and polarizable molecular mechanics studies. Proteins 2011; 79:203-20. [PMID: 21058398 DOI: 10.1002/prot.22873] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Type I phosphomannose isomerases (PMIs) are zinc-dependent metalloenzymes involved in the reversible isomerization of D-mannose 6-phosphate (M6P) and D-fructose 6-phosphate (F6P). 5-Phospho-D-arabinonohydroxamic acid (5PAH), an inhibitor endowed with nanomolar affinity for yeast (Type I) and Pseudomonas aeruginosa (Type II) PMIs (Roux et al., Biochemistry 2004; 43:2926-2934), strongly inhibits human (Type I) PMI (for which we report an improved expression and purification procedure), as well as Escherichia coli (Type I) PMI. Its K(i) value of 41 nM for human PMI is the lowest value ever reported for an inhibitor of PMI. 5-Phospho-D-arabinonhydrazide, a neutral analogue of the reaction intermediate 1,2-cis-enediol, is about 15 times less efficient at inhibiting both enzymes, in accord with the anionic nature of the postulated high-energy reaction intermediate. Using the polarizable molecular mechanics, sum of interactions between fragments ab initio computed (SIBFA) procedure, computed structures of the complexes between Candida albicans (Type I) PMI and the cyclic substrate β-D-mannopyranose 6-phosphate (β-M6P) and between the enzyme and the high-energy intermediate analogue inhibitor 5PAH are reported. Their analysis allows us to identify clearly the nature of each individual active site amino acid and to formulate a hypothesis for the overall mechanism of the reaction catalyzed by Type I PMIs, that is, the ring-opening and isomerization steps, respectively. Following enzyme-catalyzed ring-opening of β-M6P by zinc-coordinated water and Gln111 ligands, Lys136 is identified as the probable catalytic base involved in proton transfer between the two carbon atoms C1 and C2 of the substrate D-mannose 6-phosphate.
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Affiliation(s)
- Céline Roux
- Laboratoire de Chimie Bioorganique et Bioinorganique, ICMMO, Univ Paris-Sud, UMR 8182, Orsay F-91405, France
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27
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Sabirova JS, Becker A, Lünsdorf H, Nicaud JM, Timmis KN, Golyshin PN. Transcriptional profiling of the marine oil-degrading bacterium Alcanivorax borkumensis during growth on n-alkanes. FEMS Microbiol Lett 2011; 319:160-8. [DOI: 10.1111/j.1574-6968.2011.02279.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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28
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Pelissier MC, Lesley SA, Kuhn P, Bourne Y. Structural insights into the catalytic mechanism of bacterial guanosine-diphospho-D-mannose pyrophosphorylase and its regulation by divalent ions. J Biol Chem 2010; 285:27468-27476. [PMID: 20573954 DOI: 10.1074/jbc.m109.095182] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
GMP catalyzes the formation of GDP-Man, a fundamental precursor for protein glycosylation and bacterial cell wall and capsular polysaccharide biosynthesis. Crystal structures of GMP from the thermophilic bacterium Thermotoga maritima in the apo form, in complex with the substrates mannose-1-phosphate or GTP and bound with the end product GDP-Man in the presence of the essential divalent cation Mg(2+), were solved in the 2.1-2.8 A resolution range. The T. maritima GMP molecule is organized in two separate domains: a N-terminal Rossman fold-like domain and a C-terminal left-handed beta-helix domain. Two molecules associate into a dimer through a tail-to-tail arrangement of the C-terminal domains. Comparative analysis of the structures along with characterization of enzymatic parameters reveals the bases of substrate specificity of this class of sugar nucleotidyltransferases. In particular, substrate and product binding are associated with significant changes in the conformation of loop regions lining the active center and in the relative orientation of the two domains. Involvement of both the N- and C-terminal domains, coupled to the catalytic role of a bivalent metal ion, highlights the catalytic features of bacterial GMPs compared with other members of the pyrophosphorylase superfamily.
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Affiliation(s)
- Marie-Cécile Pelissier
- Architecture et Fonction des Macromolécules Biologiques, UMR-6098, CNRS, Université Aix-Marseille, F-13288 Marseille, France
| | - Scott A Lesley
- Genomics Institute of the Novartis Research Foundation, San Diego, California 92121
| | - Peter Kuhn
- Scripps Research Institute, La Jolla, California 92037
| | - Yves Bourne
- Architecture et Fonction des Macromolécules Biologiques, UMR-6098, CNRS, Université Aix-Marseille, F-13288 Marseille, France.
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Sensor kinases RetS and LadS regulate Pseudomonas syringae type VI secretion and virulence factors. J Bacteriol 2010; 192:3584-96. [PMID: 20472799 DOI: 10.1128/jb.00114-10] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas syringae pv. syringae B728a is a resident on leaves of common bean, where it utilizes several well-studied virulence factors, including secreted effectors and toxins, to develop a pathogenic interaction with its host. The B728a genome was recently sequenced, revealing the presence of 1,297 genes with unknown function. This study demonstrates that a 29.9-kb cluster of genes in the B728a genome shares homology to the novel type VI secretion system (T6SS) locus recently described for other gram-negative bacteria. Western blot analyses showed that B728a secretes Hcp, a T6SS protein, in culture and that this secretion is dependent on clpV, a gene that likely encodes an AAA(+) ATPase. In addition, we have identified two B728a sensor kinases that have homology to the P. aeruginosa proteins RetS and LadS. We demonstrate that B728a RetS and LadS reciprocally regulate the T6SS and collectively modulate several virulence-related activities. Quantitative PCR analyses indicated that RetS and LadS regulate genes associated with the type III secretion system and that LadS controls the expression of genes involved in the production of the exopolysaccharides alginate and levan. These analyses also revealed that LadS and the hybrid sensor kinase GacS positively regulate the expression of a putative novel exopolysaccharide called Psl. Plate assays demonstrated that RetS negatively controls mucoidy, while LadS negatively regulates swarming motility. A mutation in retS affected B728a population levels on the surfaces of bean leaves. A model for the LadS and RetS control of B728a virulence activities is proposed.
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Asención Diez MD, Demonte A, Giacomelli J, Garay S, Rodrígues D, Hofmann B, Hecht HJ, Guerrero SA, Iglesias AA. Functional characterization of GDP-mannose pyrophosphorylase from Leptospira interrogans serovar Copenhageni. Arch Microbiol 2009; 192:103-14. [PMID: 20035319 DOI: 10.1007/s00203-009-0534-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 12/03/2009] [Accepted: 12/07/2009] [Indexed: 11/30/2022]
Abstract
Leptospira interrogans synthesizes a range of mannose-containing glycoconjugates relevant for its virulence. A prerequisite in the synthesis is the availability of the GDP-mannose, produced from mannose-1-phosphate and GTP in a reaction catalyzed by GDP-mannose pyrophosphorylase. The gene coding for a putative enzyme in L. interrogans was expressed in Escherichia coli BL21(DE3). The identity of this enzyme was confirmed by electrospray-mass spectroscopy, Edman sequencing and immunological assays. Gel filtration chromatography showed that the dimeric form of the enzyme is catalytically active and stable. The recombinant protein was characterized as a mannose-1-phosphate guanylyltransferase. S (0.5) for the substrates were determined both in GDP-mannose pyrophosphorolysis: 0.20 mM (GDP-mannose), 0.089 mM (PPi), and 0.47 mM; and in GDP-mannose synthesis: 0.24 mM (GTP), 0.063 mM (mannose-1-phosphate), and 0.45 mM (Mg(2+)). The enzyme was able to produce GDP-mannose, IDP-mannose, UDP-mannose and ADP-glucose. We obtained a structural model of the enzyme using as a template the crystal structure of mannose-1-phosphate guanylyltransferase from Thermus thermophilus HB8. Binding of substrates and cofactor in the model agree with the pyrophosphorylases reaction mechanism. Our studies provide insights into the structure of a novel molecular target, which could be useful for detection of leptospirosis and for the development of anti-leptospiral drugs.
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Affiliation(s)
- Matías D Asención Diez
- Laboratorio de Bioquímica Microbiana, Universidad Nacional del Litoral, Santa Fe, Argentina
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31
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Fang W, Yu X, Wang B, Zhou H, Ouyang H, Ming J, Jin C. Characterization of the Aspergillus fumigatus phosphomannose isomerase Pmi1 and its impact on cell wall synthesis and morphogenesis. Microbiology (Reading) 2009; 155:3281-3293. [DOI: 10.1099/mic.0.029975-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phosphomannose isomerase (PMI) is an enzyme catalysing the interconversion of mannose 6-phosphate (Man-6-P) and fructose 6-phosphate (Fru-6-P). The reaction catalysed by PMI is the first committed step in the synthesis of mannose-containing sugar chains and provides a link between glucose metabolism and mannosylation. In this study, the pmi1 gene was identified to encode PMI in the human fungal pathogen Aspergillus fumigatus. Characterization of A. fumigatus Pmi1 expressed in Escherichia coli revealed that this PMI mainly catalysed the conversion of Fru-6-P to Man-6-P and that its binding affinity for Man-6-P was similar to that of yeast PMIs, but different to those of PMIs from bacteria or animals. Loss of pmi1 was lethal unless Man was provided in the growth medium. However, a Δpmi1 mutant cell showed a significantly reduced growth rate at a high concentration of Man. Biochemical analysis revealed that both inadequate and replete Man led to an accumulation of intracellular Man-6-P and a reduction in the amount of α-glucan in the cell wall. Uncoupling of the link between energy production and glycosylation by deletion of the pmi1 gene led to phenotypes such as defects in cell wall integrity, abnormal morphology and reduced conidiation. Our results reveal that PMI activity is essential for viability and plays a central regulatory role in both cell wall synthesis and energy production in A. fumigatus.
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Affiliation(s)
- Wenxia Fang
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Xiaoying Yu
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Bin Wang
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Hui Zhou
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Haomiao Ouyang
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Jia Ming
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Cheng Jin
- Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
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Synthesis and evaluation of non-hydrolyzable D-mannose 6-phosphate surrogates reveal 6-deoxy-6-dicarboxymethyl-D-mannose as a new strong inhibitor of phosphomannose isomerases. Bioorg Med Chem 2009; 17:7100-7. [PMID: 19783448 DOI: 10.1016/j.bmc.2009.09.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Revised: 08/28/2009] [Accepted: 09/03/2009] [Indexed: 11/23/2022]
Abstract
Non-hydrolyzable d-mannose 6-phosphate analogues in which the phosphate group was replaced by a phosphonomethyl, a dicarboxymethyl, or a carboxymethyl group were synthesized and kinetically evaluated as substrate analogues acting as potential inhibitors of type I phosphomannose isomerases (PMIs) from Saccharomyces cerevisiae and Escherichia coli. While 6-deoxy-6-phosphonomethyl-d-mannose and 6-deoxy-6-carboxymethyl-D-mannose did not inhibit the enzymes significantly, 6-deoxy-6-dicarboxymethyl-D-mannose appeared as a new strong competitive inhibitor of both S. cerevisiae and E. coli PMIs with K(m)/K(i) ratios of 28 and 8, respectively. We thus report the first malonate-based inhibitor of an aldose-ketose isomerase to date. Phosphonomethyl mimics of the 1,2-cis-enediolate high-energy intermediate postulated for the isomerization reaction catalyzed by PMIs were also synthesized but behave as poor inhibitors of PMIs. A polarizable molecular mechanics (SIBFA) study was performed on the complexes of d-mannose 6-phosphate and two of its analogues with PMI from Candida albicans, an enzyme involved in yeast infection homologous to S. cerevisiae and E. coli PMIs. It shows that effective binding to the catalytic site occurs with retention of the Zn(II)-bound water molecule. Thus the binding of the hydroxyl group on C1 of the ligand to Zn(II) should be water-mediated. The kinetic study reported here also suggests the dianionic character of the phosphate surrogate as a likely essential parameter for strong binding of the inhibitor to the enzyme active site.
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King JD, Kocíncová D, Westman EL, Lam JS. Review: Lipopolysaccharide biosynthesis in Pseudomonas aeruginosa. Innate Immun 2009; 15:261-312. [PMID: 19710102 DOI: 10.1177/1753425909106436] [Citation(s) in RCA: 229] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Pseudomonas aeruginosa causes serious nosocomial infections, and an important virulence factor produced by this organism is lipopolysaccharide (LPS). This review summarizes knowledge about biosynthesis of all three structural domains of LPS - lipid A, core oligosaccharide, and O polysaccharides. In addition, based on similarities with other bacterial species, this review proposes new hypothetical pathways for unstudied steps in the biosynthesis of P. aeruginosa LPS. Lipid A biosynthesis is discussed in relation to Escherichia coli and Salmonella, and the biosyntheses of core sugar precursors and core oligosaccharide are summarised. Pseudomonas aeruginosa attaches a Common Polysaccharide Antigen and O-Specific Antigen polysaccharides to lipid A-core. Both forms of O polysaccharide are discussed with respect to their independent synthesis mechanisms. Recent advances in understanding O-polysaccharide biosynthesis since the last major review on this subject, published nearly a decade ago, are highlighted. Since P. aeruginosa O polysaccharides contain unusual sugars, sugar-nucleotide biosynthesis pathways are reviewed in detail. Knowledge derived from detailed studies in the O5, O6 and O11 serotypes is applied to predict biosynthesis pathways of sugars in poorly-studied serotypes, especially O1, O4, and O13/O14. Although further work is required, a full understanding of LPS biosynthesis in P. aeruginosa is almost within reach.
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Affiliation(s)
- Jerry D King
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
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34
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Byrd MS, Sadovskaya I, Vinogradov E, Lu H, Sprinkle AB, Richardson SH, Ma L, Ralston B, Parsek MR, Anderson EM, Lam JS, Wozniak DJ. Genetic and biochemical analyses of the Pseudomonas aeruginosa Psl exopolysaccharide reveal overlapping roles for polysaccharide synthesis enzymes in Psl and LPS production. Mol Microbiol 2009; 73:622-38. [PMID: 19659934 DOI: 10.1111/j.1365-2958.2009.06795.x] [Citation(s) in RCA: 257] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Exopolysaccharides contribute significantly to attachment and biofilm formation in the opportunisitc pathogen Pseudomonas aeruginosa. The Psl polysaccharide, which is synthesized by the polysaccharide synthesis locus (psl), is required for biofilm formation in non-mucoid strains that do not rely on alginate as the principal biofilm polysaccharide. In-frame deletion and complementation studies of individual psl genes revealed that 11 psl genes, pslACDEFGHIJKL, are required for Psl production and surface attachment. We also present the first structural analysis of the psl-dependent polysaccharide, which consists of a repeating pentasaccharide containing d-mannose, d-glucose and l-rhamnose: [See text]. In addition, we identified the sugar nucleotide precursors involved in Psl generation and demonstrated the requirement for GDP-d-mannose, UDP-d-glucose and dTDP-l-rhamnose in Psl production and surface attachment. Finally, genetic analyses revealed that wbpW restored Psl production in a pslB mutant and pslB promoted A-band LPS synthesis in a wbpW mutant, indicating functional redundancy and overlapping roles for these two enzymes. The structural and genetic data presented here provide a basis for further investigation of the Psl proteins and potential roles for Psl in the biology and pathogenesis of P. aeruginosa.
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Affiliation(s)
- Matthew S Byrd
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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35
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Substrate specificity of a mannose-6-phosphate isomerase from Bacillus subtilis and its application in the production of L-ribose. Appl Environ Microbiol 2009; 75:4705-10. [PMID: 19447949 DOI: 10.1128/aem.00310-09] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The uncharacterized gene previously proposed as a mannose-6-phosphate isomerase from Bacillus subtilis was cloned and expressed in Escherichia coli. The maximal activity of the recombinant enzyme was observed at pH 7.5 and 40 degrees C in the presence of 0.5 mM Co(2+). The isomerization activity was specific for aldose substrates possessing hydroxyl groups oriented in the same direction at the C-2 and C-3 positions, such as the d and l forms of ribose, lyxose, talose, mannose, and allose. The enzyme exhibited the highest activity for l-ribulose among all pentoses and hexoses. Thus, L-ribose, as a potential starting material for many L-nucleoside-based pharmaceutical compounds, was produced at 213 g/liter from 300-g/liter L-ribulose by mannose-6-phosphate isomerase at 40 degrees C for 3 h, with a conversion yield of 71% and a volumetric productivity of 71 g liter(-1) h(-1).
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36
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Mizanur RM, Pohl NLB. Phosphomannose isomerase/GDP-mannose pyrophosphorylase from Pyrococcus furiosus: a thermostable biocatalyst for the synthesis of guanidinediphosphate-activated and mannose-containing sugar nucleotides. Org Biomol Chem 2009; 7:2135-9. [PMID: 19421452 DOI: 10.1039/b822794b] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein we present an analysis of the chemical function of a recombinant bifunctional phosphomannose isomerase/GDP-mannose pyrophosphorylase (manC) from Pyrococcus furiosus DSM 3638 and its use in the synthesis of guanidinediphospho-hexoses and a range of nucleotidediphospho-mannoses. This enzyme is unusually promiscuous in both its nucleotide triphosphate (NTP) and sugar-1-phosphate acceptance. It accepts all five naturally occurring NTPs (ATP, CTP, GTP, dTTP and UTP) and a range of sugar-1-phosphates (glucose-, mannose-, galactose-, glucosamine-, N-acetylglucosamine- and fucose-1-phosphate). A truncated GDP-mannose pyrophosphorylase domain of the whole length enzyme showed almost 100-fold less sugar nucleotidyltransferase activity with only GTP and mannose 1-phosphate as substrates. The temperature stability and inherently broad substrate tolerance of this archaeal enzyme make it an effective reagent for the rapid chemoenzymatic synthesis of a range of natural and unnatural sugar nucleotides that are challenging to make by chemical means alone.
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Affiliation(s)
- Rahman M Mizanur
- Department of Chemistry and Plant Sciences Institute, Gilman Hall, Iowa State University, Ames, Iowa 50011-3111, USA
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37
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Alginate Production: Precursor Biosynthesis, Polymerization and Secretion. ALGINATES: BIOLOGY AND APPLICATIONS 2009. [DOI: 10.1007/978-3-540-92679-5_2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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38
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Identification of amino acid residues important for the phosphomannose isomerase activity of PslB in Pseudomonas aeruginosa PAO1. FEBS Lett 2008; 582:3479-83. [PMID: 18801364 DOI: 10.1016/j.febslet.2008.09.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Revised: 09/09/2008] [Accepted: 09/09/2008] [Indexed: 11/20/2022]
Abstract
Phosphomannose isomerase (PMI) plays a pivotal role in biosynthesis of GDP-mannose, an important precursor of many polysaccharides. We demonstrate in this study that Pseudomonas aeruginosa pslB encodes a protein with GDP-mannose pyrophosphorylase/PMI dual activities. The PMI activity is Co2+-dependent and could be inhibited by GDP-mannose in a competitive manner. Furthermore, the activity could be inactivated by 2,3-butanedione suggesting the presence of a catalytic Arg residue. Site-specific mutations at R373, R472, R479, E410, H411, N433 and E458 increase the KM approximately 8-20-fold. The PMI activity of PslB was completely diminished with a R408K or R408A, reflecting the importance of this residue in catalysis. Overall, these results provide a basis for understanding the catalytic mechanism of PMI.
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Oglesby LL, Jain S, Ohman DE. Membrane topology and roles of Pseudomonas aeruginosa Alg8 and Alg44 in alginate polymerization. MICROBIOLOGY-SGM 2008; 154:1605-1615. [PMID: 18524915 DOI: 10.1099/mic.0.2007/015305-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Mucoid strains of Pseudomonas aeruginosa that overproduce alginate are associated with chronic pulmonary disease (e.g. cystic fibrosis). Mutants defective in one of several periplasmic proteins (AlgKGX) for alginate secretion release alginate fragments due to the activity of an alginate lyase (AlgL) in the periplasm, which cleaves the newly formed polymers. However, mutants defective in Alg8 or Alg44 did not secrete polymer or alginate fragments, suggesting that both these membrane proteins have a role in the polymerization reaction. A model for the membrane topology of Alg8, a glycosyltransferase (GT), was constructed using PhoA fusions. This provided evidence for a large cytoplasmic loop containing the active domains predicted for beta-GTs such as Alg8 and five transmembrane (TM) domains, one of which resembles a cleavable signal peptide. The C-terminal TM domain of Alg8 was critical for the polymerization reaction in vivo. Alanine substitution mutagenesis showed that all of the predicted active site residues in the widely spaced D, DxD, D, LxxRW motif were required for polymerization activity in vivo, and two of these substitutions also affected Alg8 protein stability. A membrane topology model for Alg44 was also constructed using PhoA fusions, and this showed a central TM domain and predicted an N-terminal TM domain that may be a membrane anchor. An N-terminal PilZ domain in Alg44 for c-di-GMP [bis-(3',5')-cyclic dimeric GMP] binding, which is required for alginate synthesis, was localized to the cytoplasmic loop. The long periplasmic C terminus of Alg44 contains a region similar to membrane fusion proteins (MFPs) of multi-drug efflux systems, which predicts the possibility of its interaction with another protein in this compartment. A Western blot analysis of the outer-membrane porin AlgE showed reduced AlgE levels in the alg44 mutant, whereas expression of Alg44 in trans restored AlgE within the cell. C-terminal truncations of Alg44 as small as 24 amino acids blocked alginate polymerization in vivo, indicating a critical role for the MFP domain. These studies suggest that Alg44 may act as a co-polymerase in concert with Alg8, the major GT, and that both inner-membrane proteins are required in vivo for the polymerization reaction leading to alginate production.
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Affiliation(s)
- Lashanda L Oglesby
- McGuire Veterans Affairs Medical Center, Richmond, VA 23249, USA
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0678, USA
| | - Sumita Jain
- McGuire Veterans Affairs Medical Center, Richmond, VA 23249, USA
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0678, USA
| | - Dennis E Ohman
- McGuire Veterans Affairs Medical Center, Richmond, VA 23249, USA
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0678, USA
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40
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Functional analysis of the Burkholderia cenocepacia J2315 BceAJ protein with phosphomannose isomerase and GDP-D-mannose pyrophosphorylase activities. Appl Microbiol Biotechnol 2008; 80:1015-22. [PMID: 18668237 DOI: 10.1007/s00253-008-1612-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 07/04/2008] [Accepted: 07/07/2008] [Indexed: 10/21/2022]
Abstract
The bceA(J) gene from the cystic fibrosis isolate Burkholderia cenocepacia J2315 encodes a 56-kDa bifunctional protein, with phosphomannose isomerase (PMI) and guanosine diphosphate (GDP)-mannose pyrophosphorylase (GMP) activities, a new member of the poorly characterised type II PMI class of proteins. Due to the lack of homology between the type II PMIs and the human PMI, this class of proteins are being regarded as interesting potential targets to develop new antimicrobials. The BceA(J) protein conserves the four typical motifs of type II PMIs: the pyrophosphorylase signature, the GMP active site, the PMI active site and the zinc-binding motif. After overproduction of BceA(J) by Escherichia coli as a histidine tag derivative, the protein was purified to homogeneity by affinity chromatography. The GMP activity is dependent on the presence of Mg(2+) or Ca(2+) as cofactors, while the PMI activity uses a broader range of divalent ions, in the order of activation Mg(2+) > Ca(2+) > Mn(2+) > Co(2+) > Ni(2+). The kinetic parameters K(m), V(max) and K(cat)/K(m) for the PMI and GMP activities were determined. Results suggest that the enzyme favours the formation of GDP-mannose instead of mannose catabolism, thus channelling precursors to the formation of glycoconjugates.
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41
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Evaluation of protein safety in the context of agricultural biotechnology. Food Chem Toxicol 2008; 46 Suppl 2:S71-97. [DOI: 10.1016/j.fct.2008.01.045] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 01/16/2008] [Accepted: 01/19/2008] [Indexed: 11/15/2022]
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Gresh N, Cisneros GA, Darden TA, Piquemal JP. Anisotropic, Polarizable Molecular Mechanics Studies of Inter- and Intramolecular Interactions and Ligand-Macromolecule Complexes. A Bottom-Up Strategy. J Chem Theory Comput 2007; 3:1960-1986. [PMID: 18978934 PMCID: PMC2367138 DOI: 10.1021/ct700134r] [Citation(s) in RCA: 281] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
We present an overview of the SIBFA polarizable molecular mechanics procedure, which is formulated and calibrated on the basis of quantum chemistry (QC). It embodies nonclassical effects such as electrostatic penetration, exchange-polarization, and charge transfer. We address the issues of anisotropy, nonadditivity, and transferability by performing parallel QC computations on multimolecular complexes. These encompass multiply H-bonded complexes and polycoordinated complexes of divalent cations. Recent applications to the docking of inhibitors to Zn-metalloproteins are presented next, namely metallo-beta-lactamase, phosphomannoisomerase, and the nucleocapsid of the HIV-1 retrovirus. Finally, toward third-generation intermolecular potentials based on density fitting, we present the development of a novel methodology, the Gaussian electrostatic model (GEM), which relies on ab initio-derived fragment electron densities to compute the components of the total interaction energy. As GEM offers the possibility of a continuous electrostatic model going from distributed multipoles to densities, it allows an inclusion of short-range quantum effects in the molecular mechanics energies. The perspectives of an integrated SIBFA/GEM/QM procedure are discussed.
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Affiliation(s)
- Nohad Gresh
- Laboratoire de Pharmacochimie Moléculaire et Cellulaire, U648 INSERM, UFR Biomédicale, Université René-Descartes, 45, rue des Saints-Pères, 75006 Paris, France, Laboratory of Structural Biology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, and Laboratoire de Chimie Théorique, Université Pierre-et-Marie-Curie, UMR 7616 CNRS, case courrier 137, 4, place Jussieu, 75252 Paris, France
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Roux C, Gresh N, Perera LE, Piquemal JP, Salmon L. Binding of 5-phospho-D-arabinonohydroxamate and 5-phospho-D-arabinonate inhibitors to zinc phosphomannose isomerase from Candida albicans studied by polarizable molecular mechanics and quantum mechanics. J Comput Chem 2007; 28:938-57. [PMID: 17253648 DOI: 10.1002/jcc.20586] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Type I phosphomannose isomerase (PMI) is a Zn-dependent metalloenzyme involved in the isomerization of D-fructose 6-phosphate to D-mannose 6-phosphate. One of our laboratories has recently designed and synthesized 5-phospho-D-arabinonohydroxamate (5PAH), an inhibitor endowed with a nanomolar affinity for PMI (Roux et al., Biochemistry 2004, 43, 2926). By contrast, the 5-phospho-D-arabinonate (5PAA), in which the hydroxamate moiety is replaced by a carboxylate one, is devoid of inhibitory potency. Subsequent biochemical studies showed that in its PMI complex, 5PAH binds Zn(II) through its hydroxamate moiety rather than through its phosphate. These results have stimulated the present theoretical investigation in which we resort to the SIBFA polarizable molecular mechanics procedure to unravel the structural and energetical aspects of 5PAH and 5PAA binding to a 164-residue model of PMI. Consistent with the experimental results, our theoretical studies indicate that the complexation of PMI by 5PAH is much more favorable than by 5PAA, and that in the 5PAH complex, Zn(II) ligation by hydroxamate is much more favorable than by phosphate. Validations by parallel quantum-chemical computations on model of the recognition site extracted from the PMI-inhibitor complexes, and totaling up to 140 atoms, showed the values of the SIBFA intermolecular interaction energies in such models to be able to reproduce the quantum-chemistry ones with relative errors < 3%. On the basis of the PMI-5PAH SIBFA energy-minimized structure, we report the first hypothesis of a detailed view of the active site of the zinc PMI complexed to the high-energy intermediate analogue inhibitor, which allows us to identify active site residues likely involved in the proton transfer between the two adjacent carbons of the substrates.
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Affiliation(s)
- Celine Roux
- Laboratoire de Chimie Bioorganique et Bioinorganique, CNRS-UMR 8182, Institut de Chimie Moléculaire et des Matériaux d'Orsay, Bâtiment 420, Université Paris-Sud XI, 15 rue Georges Clémenceau, 91405 Orsay, France
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Sousa SA, Moreira LM, Wopperer J, Eberl L, Sá-Correia I, Leitão JH. The Burkholderia cepacia bceA gene encodes a protein with phosphomannose isomerase and GDP-D-mannose pyrophosphorylase activities. Biochem Biophys Res Commun 2006; 353:200-6. [PMID: 17184737 DOI: 10.1016/j.bbrc.2006.12.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Accepted: 12/04/2006] [Indexed: 11/18/2022]
Abstract
The bceA gene is part of the Burkholderia cepacia IST408 exopolysaccharide (EPS) biosynthetic cluster. It encodes a 55.3-kDa bifunctional protein (type II PMI family) with phosphomannose isomerase (PMI) and GDP-mannose pyrophosphorylase (GMP) activities. GMP activity is strongly dependent on the presence of Ca(2+) or Mn(2+), while PMI activity can use a broader variety of divalent cations (Ca(2+)>Mn(2+)>Mg(2+)>Co(2+)>Ni(2+)). The lack of a functional bceA gene does not affect EPS production yield in a non-polar insertion bceA mutant. The in silico search for putative bceA homologues revealed the presence of 2-5 bceA orthologues in the Burkholderia genomes available. This suggests that in B. cepacia IST408 putative bceA functional homologues may compensate the bceA mutation. However, the viscosity of aqueous solutions prepared with the EPS produced by the bceA mutant was significantly reduced compared with wild-type biopolymer and the mutant forms biofilms with a size reduced by 6-fold.
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Affiliation(s)
- Sílvia A Sousa
- IBB-Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
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Shankar S, Ye RW, Schlictman D, Chakrabarty AM. Exopolysaccharide alginate synthesis in Pseudomonas aeruginosa: enzymology and regulation of gene expression. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 70:221-55. [PMID: 8638483 DOI: 10.1002/9780470123164.ch4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- S Shankar
- Department of Microbiology and Immunology, University of Illinois, College of Medicine, Chicago, USA
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Bonofiglio L, García E, Mollerach M. Biochemical characterization of the pneumococcal glucose 1-phosphate uridylyltransferase (GalU) essential for capsule biosynthesis. Curr Microbiol 2005; 51:217-21. [PMID: 16132460 DOI: 10.1007/s00284-005-4466-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2004] [Accepted: 02/16/2005] [Indexed: 11/29/2022]
Abstract
The glucose 1-phosphate uridylyltransferase (GalU) is absolutely required for the biosynthesis of capsular polysaccharide, the sine qua non virulence factor of Streptococcus pneumoniae. The pneumococcal GalU protein was overexpressed in Escherichia coli, and purified. GalU showed a pI of 4.23, and catalyzed the reversible formation of UDP-glucose and pyrophosphate from UTP and glucose 1-phosphate with K(m) values of 0.4 mM: for UDP-glucose, 0.26 mM: for pyrophosphate, 0.19 mM: for glucose 1-phosphate, and 0.24 mM: for UTP. GalU has an optimum pH of 8-8.5, and requires Mg(2+) for activity. Neither ADP-glucose nor TDP-glucose is utilized as substrates in vitro. The purification of GalU represents a fundamental step to provide insights on drug design to control the biosynthesis of the main pneumococcal virulence factor.
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Affiliation(s)
- Laura Bonofiglio
- Cátedra de Microbiología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina
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Ramsey DM, Wozniak DJ. Understanding the control of Pseudomonas aeruginosa alginate synthesis and the prospects for management of chronic infections in cystic fibrosis. Mol Microbiol 2005; 56:309-22. [PMID: 15813726 DOI: 10.1111/j.1365-2958.2005.04552.x] [Citation(s) in RCA: 284] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Decades of research have been dedicated to the study of the opportunistic pathogen Pseudomonas aeruginosa, a Gram-negative, environmental bacterium that secretes the exopolysaccharide alginate during chronic lung infection of cystic fibrosis (CF) patients. Although P. aeruginosa utilizes a variety of factors to establish a successful infection in the lungs of CF patients, alginate has stood out as one of the best-studied prognostic indicators of chronic lung infection. While the genetics, biosynthesis and regulation of alginate are well understood, questions still remain concerning its role in biofilm development and its potential as a therapeutic target. The purpose of this review is to provide a brief summary of alginate biosynthesis and regulation, and to highlight recent discoveries in the areas of alginate production, biofilm formation and vaccine design. This information is placed in context with a proposed P. aeruginosa infectious pathway, highlighting avenues for the use of existing therapies as well as the potential for novel agents to reduce or eliminate chronic infections in CF patients.
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Affiliation(s)
- Deborah M Ramsey
- Department of Microbiology and Immunology, Wake Forest University School of Medicine, Medical Center Blvd. Winston-Salem, NC 27157, USA
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Roux C, Lee JH, Jeffery CJ, Salmon L. Inhibition of Type I and Type II Phosphomannose Isomerases by the Reaction Intermediate Analogue 5-Phospho-d-Arabinonohydroxamic Acid Supports a Catalytic Role for the Metal Cofactor. Biochemistry 2004; 43:2926-34. [PMID: 15005628 DOI: 10.1021/bi035688h] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The phosphomannose isomerases (PMI) comprise three families of proteins: type I, type II, and type III PMIs. Members of all three families catalyze the reversible isomerization of D-mannose 6-phosphate (M6P) and D-fructose 6-phosphate (F6P) but share little or no sequence identity. Because (1) PMIs are essential for the survival of several microorganisms, including yeasts and bacteria, and (2) the PMI enzymes from several pathogens do not share significant sequence identity to the human protein, PMIs have been considered as potential therapeutic targets. Elucidation of the catalytic and regulatory mechanisms of the different types of PMIs is strongly needed for rational species-specific drug design. To date, inhibition and crystallographic studies of all PMIs are still largely unexplored. As part of our research program on aldose-ketose isomerases, we report in this paper the evaluation of two new inhibitors of type I and type II PMIs from baker's yeast and Pseudomonas aeruginosa, respectively. We found that 5-phospho-D-arabinonohydroxamic acid (5PAH), which is the most potent inhibitor of phosphoglucose isomerase (PGI), is by far the best inhibitor ever reported of both type I and type II PMI-catalyzed isomerization of M6P to F6P. 5PAH, which has an inhibition constant at least 3 orders of magnitude smaller than that of previously reported PMI inhibitors, may be the first high-energy intermediate analogue inhibitor of the enzymes. We also tested the related molecule 5-phospho-D-arabinonate (5PAA), which is a strong competitive inhibitor of PGI, and found that it does not inhibit either PMI. All together, our results are consistent with a catalytic role for the metal cofactor in PMI activity.
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Affiliation(s)
- Céline Roux
- Laboratoire de Chimie Bioorganique et Bioinorganique, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8124, Institut de Chimie Moléculaire et des Matériaux d'Orsay, Bâtiment 420, Université Paris-Sud XI, 91405 Orsay, France
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Gimmestad M, Sletta H, Ertesvåg H, Bakkevig K, Jain S, Suh SJ, Skjåk-Braek G, Ellingsen TE, Ohman DE, Valla S. The Pseudomonas fluorescens AlgG protein, but not its mannuronan C-5-epimerase activity, is needed for alginate polymer formation. J Bacteriol 2003; 185:3515-23. [PMID: 12775688 PMCID: PMC156231 DOI: 10.1128/jb.185.12.3515-3523.2003] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial alginates are produced as 1-4-linked beta-D-mannuronan, followed by epimerization of some of the mannuronic acid residues to alpha-L-guluronic acid. Here we report the isolation of four different epimerization-defective point mutants of the periplasmic Pseudomonas fluorescens mannuronan C-5-epimerase AlgG. All mutations affected amino acids conserved among AlgG-epimerases and were clustered in a part of the enzyme also sharing some sequence similarity to a group of secreted epimerases previously reported in Azotobacter vinelandii. An algG-deletion mutant was constructed and found to produce predominantly a dimer containing a 4-deoxy-L-erythro-hex-4-enepyranosyluronate residue at the nonreducing end and a mannuronic acid residue at the reducing end. The production of this dimer is the result of the activity of an alginate lyase, AlgL, whose in vivo activity is much more limited in the presence of AlgG. A strain expressing both an epimerase-defective (point mutation) and a wild-type epimerase was constructed and shown to produce two types of alginate molecules: one class being pure mannuronan and the other having the wild-type content of guluronic acid residues. This formation of two distinct classes of polymers in a genetically pure cell line can be explained by assuming that AlgG is part of a periplasmic protein complex.
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Affiliation(s)
- Martin Gimmestad
- Department of Biotechnology, Norwegian University of Science and Technology, Trondheim, Norway
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Ballicora MA, Iglesias AA, Preiss J. ADP-glucose pyrophosphorylase, a regulatory enzyme for bacterial glycogen synthesis. Microbiol Mol Biol Rev 2003; 67:213-25, table of contents. [PMID: 12794190 PMCID: PMC156471 DOI: 10.1128/mmbr.67.2.213-225.2003] [Citation(s) in RCA: 182] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The accumulation of alpha-1,4-polyglucans is an important strategy to cope with transient starvation conditions in the environment. In bacteria and plants, the synthesis of glycogen and starch occurs by utilizing ADP-glucose as the glucosyl donor for elongation of the alpha-1,4-glucosidic chain. The main regulatory step takes place at the level of ADP-glucose synthesis, a reaction catalyzed by ADP-Glc pyrophosphorylase (PPase). Most of the ADP-Glc PPases are allosterically regulated by intermediates of the major carbon assimilatory pathway in the organism. Based on specificity for activator and inhibitor, classification of ADP-Glc PPases has been expanded into nine distinctive classes. According to predictions of the secondary structure of the ADP-Glc PPases, they seem to have a folding pattern common to other sugar nucleotide pyrophosphorylases. All the ADP-Glc PPases as well as other sugar nucleotide pyrophosphorylases appear to have evolved from a common ancestor, and later, ADP-Glc PPases developed specific regulatory properties, probably by addition of extra domains. Studies of different domains by construction of chimeric ADP-Glc PPases support this hypothesis. In addition to previous chemical modification experiments, the latest random and site-directed mutagenesis experiments with conserved amino acids revealed residues important for catalysis and regulation.
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Affiliation(s)
- Miguel A Ballicora
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
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